Generally, vacuum cleaners generate a suction force to draw-in dirt from a surface to be cleaned. The vacuum cleaners are provided with a dust collecting apparatus that separates and collects dust, dirt, particulates, debris, contaminants, and other similar matter from the air drawn into the vacuum cleaner. The term “dust” will be used herein to refer collectively to dust, dirt, particulates, debris, contaminants, and other similar matter that can be entrained with the air suctioned by the vacuum cleaner.
Cyclone separating apparatuses are well known as dust collecting apparatuses for a vacuum cleaner. The conventional cyclone separating apparatus can effectively remove relatively large dust from the drawn-in air but often cannot effectively remove fine dust.
To remove fine dust more effectively, a multi-cyclone separating apparatus has been developed. The multi-cyclone separating apparatus has a first cyclone to remove relatively large dust and a plurality of second cyclones to remove fine dust from the air discharged from the first cyclone. An example of the conventional multi-cyclone separating apparatus is presented in Korean Patent Publication No. 10-2005-25711.
However, in the conventional multi-cyclone separating apparatus for a vacuum cleaner, air enters and is discharged through an upper portion of the first cyclone. Because the air whirls downward and then has move upward to exit, the air path prevents high dust separating efficiency. Also, the dust separated from the first cyclone is collected in a space in fluid communication with where the air is whirling. Thus, the collected dust impedes the whirling of the air.
Therefore, there is a need for a vacuum cleaner having a cyclone separating apparatus that can more effectively separate dust from drawn-in air and that can collect dust without affecting the whirling air.